In 1956, honey bees of the African subspecies A. m. scutellata were imported to Brazil, and their descendents subsequently spread to South, Central, and North America. This invasion sparked significant academic controversy, particularly concerning the genetic composition of the expanding population. We review the biogeography and intraspecific phylogeny of Apis mellifera in the Old World as it pertains to African-derived bees in the Americas, the methods used to study gene flow between European-derived and African-derived populations in the New World, and the techniques used in identification of African-derived bees.

The genus Lobogonius Stål is revised and 3 new species collected in New Guinea and Irian Jaya are described in the tribe Colpurini (Coreidae); new records for Lobogonius egregius (Stål) are given; a key to the known species is included; dorsal habitus, pronotum, male genital capsule, and female genital plates are illustrated.

Four new species of Nemapalpus are described; acaenohybos, stenygros and rondanica from Brazil, and phoenimimos from Colombia. N. nearcticus, originally found in Florida, is recorded in the Bahamas. A synopsis of all New World species and key to males is provided.

The male of Coenaletes caribaeus is described and illustrated. It is recorded for the first time from Mexico, with specimens from hermit crabs Coenobita clypeatus, from beaches in Quintana Roo. Drawings and scanning electron microscope pictures are included.

Analyses of intraspecific and interspecific mandible allometry and dimorphism for natural population samples of 45 species in 3 representative genera of the stag beetle family Lucanidae confirmed that conventional taxonomists have been identifying groups of species sharing the same intraspecific allometry and dimorphism as a genus. Although there was extensive variation, both intraspecific and interspecific, in male mandible morphology, covariance analyses indicated that a high proportion (87, 89, and 91% in the 3 genera studied) of the mandible length variance of all the individuals of all the species within the same genus was accounted for by the common generic allometry and dimorphism. This highly parallel nature of intraspecific allometry and dimorphism with the interspecific variation within the same genus suggests that each genus of Lucanidae is characterized by its own basic allometric and dimorphic program, and all the variations within genus, whether they are intraspecific or interspecific, follow this basic program. In stag beetles, where an individual adult morphology is fixed and mostly determined by the length and nutritional condition of the larval period, the broad sequential and dimorphic variation in male adult mandibles, seen within a given intraspecific population as a static allometry, may be also considered as an expression of the species ontogenetic program observable in a static form. The abundance of shared morphological traits among species of the same genus suggests the possibility of ontogeny functioning as a phylogenetic constraint. Genera in the Lucanidae are quantitatively describable, and possibly developmentally definable, biological entities.

A neotype is designated for Bracon (Toxoneuron) viator Say and a detailed redescription is provided. A lectotype for Toxoneuron bicolor Szépligeti is also designated, and the transfer of Cardiochiles nigriceps Viereck to the genus Toxoneuron is discussed. Morphological differences between T. bicolor and T. nigriceps are very minor, suggesting a potential synonymy, with bicolor as the senior synonym. Though biological data on T. bicolor are lacking, distributional data indicate that differences in host specificity could be used to elucidate the relationship between these 2 nominal species.

Studies on growth and development of Campoletis sonorensis (Cameron) in various instar Heliothis virescens (F.) larvae were conducted. The behavior and morphological changes of the parasitized host was also evaluated. The results indicate that the host’s age at the time of parasitism apparently influenced the development and subsequent fitness of the parasitoid. When initiating development in 3rd or 4th instar hosts, the parasitoid developed significantly slower than when initiating in 1st instar hosts. Furthermore, when developing in 3rd or 4th instar hosts, the parasitoid developed significantly faster during embryonic and 1st instar stages, and significantly slower during the 2nd, 3rd, and 4th instar stages than those developing in 1st instar hosts. In younger hosts, parasitoids also produced a significantly reduced body length, weight, longevity, and egg production estimate. Parasitism of H. virescens larvae by C. sonorensis changed host’s morphology and behavior allowing easy identification of parasitized individuals and estimation of the age of the developing parasitoid within its host.

Hydroptila consimilis Mosely, Ochrotrichia spinosa (Ross), and O. wojcickyi Blickle exhibited a close association with the appearance of the filamentous chlorophyte Cladophora (April to June) in a small woodland stream in northeastern Ohio. Laboratory rearings showed that these microcaddisflies displayed similar life cycles and exhibited hypermetamorphosis. H. consimilis mandibles are specialized for piercing individual cells within filaments of Cladophora to facilitate removal of cellular contents, whereas Ochrotrichia spp. have robustly cusped mandibles suited for piercing Cladophora and scraping diatoms from benthic substrates. Proportional similarity analysis of videotaped behavior illustrated that the feeding habits of third-instar Ochrotrichia exhibited a low similarity (0.44) to the other instars tested (Ochrotrichia fifth and Hydroptila first, third, and fifth) because of their frequent consumption of diatoms (17% of feeding efforts); all other instars tested were highly similar to each other (0.72–0.86). This division of trophic resources (i.e., differential use of diatoms versus Cladophora) minimized niche overlap between the two genera. All instars of H. consimilis and Ochrotrichia spp. fed heavily on the apical (therefore the smallest) cells of Cladophora filaments, and the time required to consume cells decreased significantly as larvae matured (P < 0.05). Larval Hydroptilidae are well adapted morphologically and behaviorally to consume Cladophora, and these algal filaments appear to represent a heterogeneous food source just as terrestrial host plants are for the array of phytophagous insects that use them.

To explore the richness and geographic turnover of dung beetle assemblages (Scarabaeinae and Aphodiinae) inhabiting the Western Iberian peninsula, a latitudinal north–south transect was carried out in Portuguese territory. Estimators of alpha, beta, and gamma diversities were used, as well as the ratio Scarabaeinae/Aphodiinae, which puts into evidence some dung beetle community spatial characteristics. Clustering methods were also used to ascertain relationships between biogeographical Portuguese regions and geographical patterns of species replacement. Although Scarabaeinae appears mainly responsible for overall and regional richness, Aphodiinae richness was rather low everywhere except for the southernmost plot of the transect investigated. The scarcity of Aphodiinae species is reflected in the Scarabaeinae/Aphodiinae ratio, a score that is, however, clearly biased toward the Aphodiinae in almost all the Iberian Peninsula. For this reason the pairwise turnover in species composition between sites is mainly determined by the variation in Scarabaeinae species. Peaks of β-diversity, especially for Scarabaeinae, and clusters from dendrograms are highly consistent with physioclimatic subregions of Portugal, thus suggesting a correspondence between biogeographic and environmental boundaries.

A study of the biology of Tropisternus lateralis nimbatus (Say), a hydrophilid beetle, was conducted in a playa on the southern high plains of Texas from early June 1995 through early September 1995. Mechanism of colonization, tolerance/avoidance to drought, larval density, and secondary production were analyzed. T. lateralis colonized playas from surrounding aquatic habitats and avoided drought through aerial dispersion. Colonization of the playa was immediate. Once in the playa, larval density increased over time. Estimated secondary production for T. lateralis in the playa was 1.86 g/m²/0.25 yr with a mean standing stock biomass of 0.0819 g/m². The cohort production interval was 14 d, resulting in an estimate of 7 discrete generations during playa fill.

We studied the gut contents of adults of 12 stonefly species of the superfamily Nemouroidea, belonging to 3 different families: Nemouridae (4 species), Capniidae (2 species), and Leuctridae (6 species) from the Sierra Nevada Mountains in Spain (southern Iberian Peninsula). For each species, we describe the male and female diet. After determining and quantifying the different components, we deduced that feeding is important among adults in this superfamily, and that the diet is varied, with cyanolichens and cyanophyceae being prominent, and hyphae and spores of Ascomycetes sometimes eaten, whereas pollen is amply consumed by some spring or spring–summer species.

Centris bicornuta Mocsary nests in preexisting holes in wood. We present data to suggest that females prefer previously used nest holes of the same species. Further, females appear to be intensely competitive and sometimes usurp nests of other females, using the resources of the last provisioned cell by opening and replacing the extant egg. Completed nests have a series of provisioned cells followed by a solid plug near the entrance to the nest. Immediately outside the solid plug is a 3–5 mm thick plug of a custardlike oily material. We provide evidence that this oily material may play an important role in reducing nest usurpation.

The development, survival, and reproduction of the psocid Liposcelis bostrychophila Badonnel were evaluated at 8 constant temperatures (17.5, 20, 22.5, 25, 27.5, 30, 32.5, and 35°C). The population reared at 17.5°C failed to develop or reproduce. Between 20 and 35°C, developmental period from egg to adult varied from 41.9 d at 20°C to 18.1 d at 32°C. Based on a nonlinear model, the lower-temperature developmental thresholds from egg, 1st through 4th stadia, and combined immature stages were estimated at 14.8, 17.4, 14.6, 15.5, 17.4, and 15.5°C, respectively; the upper temperature thresholds ranged from 36.4 to 38.8°C. The survival from egg to adult was 82.9% at 27.5°C; 37.4 and 50.7% at 20 and 35°C, respectively. After emergence the adult had a preoviposition period that ranged from 17.9 d at 20°C to 3.3 d at 27.5°C. L. bostrychophila produced the most eggs (74.7) at 27.5°C and the fewest (51.9) at 20°C. The population reared at 30°C had the highest intrinsic rate of increase (0.0946), net reproductive rate (59.59), the shortest population doubling time (7.3 d), and shorter mean generation time (43.2 d) compared with the populations reared at 6 other constant temperatures. The populations reared at 27.5–32.5°C had type I survivorship pattern; whereas populations reared at other temperatures had type III survivorship curve as determined by a Weibull frequency distribution. The optimal range of temperature for L. bostrychophila population growth was 25–32.5°C.

This study revealed that feral aster leafhoppers, Macrosteles quadrilineatus Forbes, exposed to aster yellows phytoplasma live longer and may lay more eggs than nonexposed leafhoppers. Aster leafhoppers were reared on asters infected with either of 2 strains of aster yellows phytoplasma or uninfected asters. After eclosion, adults were placed on uninfected healthy lettuce or oat plants and transferred periodically. The life span of test leafhoppers and the number of offspring they produced were compared. Females reared on noninfected aster plants lived for an average of 19 d, those reared on ‘severe’ and ‘bolt’ strain aster yellows phytoplasma-infected plants lived 26 and 28 d, respectively. The mean number of offspring produced by females reared on the bolt strain of aster yellows phytoplasma-infected asters was almost twice the number produced by nonexposed leafhoppers. The life span of feral leafhoppers or the number of eggs laid did not differ for leafhoppers maintained on either oats or lettuce after exposure to aster yellows phytoplasma-infected asters. Female leafhoppers lived twice as long as males. Our results suggest that the aster leafhopper may have had a long association with aster yellows phytoplasma. The longer life and higher fecundity of phytoplasma-infected leafhoppers may influence disease dynamics of aster yellows in lettuce.

Phyllophaga (Coleoptera: Scarabaeidae) species were collected with a blacklight trap during 1992–1994 at a single site in a relict hardwood forest in central Iowa. There were 1,580 specimens collected, representing 13 species which ranked in proportional abundance from 43.67 to 0.06%. Simpson’s diversity index (D) for species taken in this study was D = 2.87 compared with D = 4.17 for species taken across Iowa in historical data. The disparity in the indices is attributed to the limited ecological habitat sampled compared with available habitats in Iowa. Phyllophaga balia (Say) was the most abundant species (43.67%) in the current study, whereas in the historical data it was an uncommon species (0.02%). Another species, Phyllophaga spreta (Horn), believed to be a truly rare species throughout the midwestern states, was taken in modest numbers (0.95%). This is the first report of this species in Iowa since it’s original description in 1887. Three species from the current study and 8 species derived from historical data are considered to be ecologically rare. It is suggested that the presence of P. spreta may be attributed to the habitat quality at the site.

The metamorphic programmed death of Culex pipiens (L.) alimentary canal cells was studied. Hoechst DNA, Acridine Orange, and TUNEL (terminal deoxynucleotidyl transferase mediated dUTP nick end labeling) staining of larval alimentary canal whole mounts showed that programmed death of polytene cells started during the 4th stadium. The cell death program was initiated in anterior stomach polytene cells and progressed to posterior stomach and gastric caeca polytene cells. Agarose gel electrophoresis confirmed that fragmentation of alimentary canal DNA into nucleosome size fragments occurred. Diploid nuclei of the anterior and posterior stomach increased in number during the time in which programmed death of polytene cells occurred. However, TUNEL staining showed that just before pupation there was also degradation of some diploid nuclear DNA in both the anterior and posterior stomach, which suggested that some of these cells also underwent programmed cell death. MTT (3-[4,5-Dimethylthiazol-2-yl]-2,5 diphenyltetrazolium bromide) staining of the alimentary canal indicated that mitochondrial activity persisted while polytene nuclei were degraded. In addition, histological examination of serial thick sections showed that prepupal midgut cells had vacuoles which suggested that cytoplasmic cell death occurred during metamorphosis.

Vitellogenin (Vg) concentration was determined in pupal hemolymph of female southwestern corn borer, Diatraea grandiosella (Dyar). Vitellogenin concentration increased significantly with pupal age. Vitellogenin level reached 7 mg/ml on day 7 after pupation. The vitellogenin was separable into 2 apoproteins on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), with molecular weights of 145,000 for apoVg-I and 38,000 for apoVg-II. SDS-PAGE analysis revealed that vitellogenin polypetides in female pupal hemolymph appeared to be identical to those from eggs, but were absent in male and early female pupal hemolymph. A method to quantify vitellogenin by indirect ELISA is described. Results from this study and those of a previous study suggest that juvenile hormone does not have a role in vitellogenesis but does so in choriogenesis.

The study of polygyny in Solenopsis invicta Buren has demonstrated that the attractiveness of individual co-existing queens to workers appears to play a critical role in queen nutritional status and egg production. The queen that was most attractive to workers was the queen that had a higher frequency of trophallaxis by attracting more attention and nourishment from workers. Furthermore, this trophic advantage resulted in a greater reproductive success of the dominant queen as evidenced by her higher ovipositional rate. However, this higher ovipositional rate was not associated with queen weight.

In this study we compared the anatomy and histology of the alimentary canal of Dentroctonus approximatus Dietz, D. mexicanus Hopkins, D. frontalis Zimmermann, and D. brevicomis LeConte. The results show that these species share similar characteristics, and their structural pattern is comparable to that observed in other Dendroctonus species. These 4 species have characteristics not found in other bark beetle genera in the esophagus, crop, proventriculus, and hindgut. The close relationship of the Malpighian tubules to posterior foregut, anterior midgut, and distal hindgut is also different. Additionally, the midgut of the D. frontalis complex species shows a great cellular diversity, which suggests that this region may be involved in pheromone production.

Dissection of emerging adult xiphydriid woodwasps, Xiphydria ogasawarai Matsumura, occurring in eastern, central, and western Japan during a 2- to 4-yr period, revealed that adult females possessed mycangia filled with fungal spores, whereas the mycangia were absent in males. Two masses of the spore were located on the slit-like 1st and 2nd valvulae of the ovipositor sting directly below the subgenital plate, and were covered with the ventral membranes. This is a new type of mycangia in woodwasps. The spores were globular or ovoid in shape and ≈5–30 μm in diameter, and had no clamp connections. All isolates from the mycangia of the xiphydriid populations, originating from different sites and years, developed the same colonies on potato-dextrose agar. This suggests that female adults of X. ogasawarai carry a single fungal species in their mycangia. It was also found that X. ogasawarai produced a slime-like secretion from glandular organs in the body cavity (mucus reservoir), which is homologous to that present in the Siricinae.

We combined methods of geometric morphometrics and phylogenetically controlled comparisons to examine the relationship between the shape of mandibles and material used to construct the nest for 5 Osmia Panzer species. We measured leaf- and mud-using species from 2 subgenera: in the subgenus Osmia, O. lignaria Cresson (mud-user), O. cornuta Latreille (mud-user) and O. ribifloris Cockerell (leaf-user), and in the subgenus Centrosmia, O. tanneri Sandhouse (mud-user), and O. bucephela Cresson (leaf-user). Landmark-based geometric morphometrics and multivariate statistics provided a way to compare mandible shapes, distill major shape differences and visualize mandible regions that differed most among bee species. Mandible shape differed significantly among all species based on paired comparisons of Mahalanobis distances. Principal component analysis of the shape variables (relative warps analysis) revealed greater similarity between the 2 leaf-using bees, than among the mud-users. There were however, no consistent differences between these mud- and leaf-using species. Testing with two-way multivariate analysis of variance showed that the differences in shape between the leaf- and mud-using species depended on the subgenus. A broad proximate bite surface characterized leaf-using species. No such trait was common to mud-using species. Mandibles of leaf-using species may vary less because of selection on shape, or because of functional constraints for shearing and macerating leaf material; both constraints are absent in mud-using species. Mandibles of mud-using bees may respond more to selection imposed by other aspects of bee biology.

In a study carried out on Oxybelus lamellatus Olivier in eastern Spain, males emerge before females, patrolling the potential nesting area; they form mating balls and construct sleeping burrows. Females nest during the summer in dense aggregations on flat, sandy soils with almost no vegetation. They construct their nests mainly early in the morning. When excavating the nest, they push and rake soil, including the tumulus, which is leveled before provisioning begins. After the nest has been built, females orient by engaging in circular and figure-8 flights. The nest consists of an oblique main burrow with a single cell, although females may add cells later to an established nest. The prey (males and females of Diptera: Brachycera) are carried in pedal and abdominal transport. Pedal carriage was used for lighter prey, whereas abdominal carriage (sting-carrying) was used for those of greater weight; for prey weight/wasp width ratios between 3.10 and 3.40, both types of carriage were observed. Thirty-five species included in 9 families were caught as prey. Eggs are laid in a Crabro-type (sensu Iwata 1942) position.

The implications of insects’ vision for territorial defense have been relatively little studied in the field. In the dragonfly Perithemis tenera Say we investigated whether either the angle at which an intruder was viewed by a territorial resident or the background against which it was viewed affected the detection of that intruder. Residents detected intruders at a greater distance if the intruders were directly in front of them; they also detected more intruders in front of them than from other angles. Intruders viewed against distant vegetation were detected more readily than were intruders against near vegetation. Residents detected more intruders viewed against distant vegetation than viewed against near vegetation; however, more intruders than expected were detected against near vegetation. The probability of detecting intruders depends on the angle at which they are viewed and the background behind them. Hence, there may be selection on territorial residents to adjust their orientation and space use to enhance their view of their territory and intruders.

We examined the effects of ambient temperature on the brooding behavior of male waterbugs, Belostoma flumineum Say. Male waterbugs are more likely to prematurely terminate care for small egg-pads than for larger egg-pads. Because embryogenesis and breeding season are both associated with ambient temperature, males in warmer environments may respond differently than those in cooler conditions. We studied the effects of temperature on male parental behavior by housing groups of completely and partially egg-encumbered males under different thermal regimes. Completely encumbered males rarely discarded egg-pads, regardless of ambient temperature. Partially encumbered males housed under warm ambient temperatures, however, were significantly more likely to discard the eggs than those housed under cooler conditions. These results are consistent with the hypothesis that cool ambient temperatures at the end of the breeding season elicit a terminal investment strategy.

The frequent interruption of male courtship in highly crowded mass-rearing cages of Ceratitis capitata (Wiedemann) was correlated with changes in both male courtship and female acceptance criteria in a mass-reared Costa Rican strain, in accord with previous studies of other strains. Abbreviation of courtship behavior by mass-reared males was associated with the loss of the wild-type female tendency to reject males that performed shorter courtships. Consideration of probable costs and benefits of female choice in mass-rearing cages suggests that inadvertant selection in the cages probably favored the change in female criteria because females obtained sons with more effective courtship behavior.